The present invention relates to a lighting control system that controls a lighting device.
A lighting control system controls the output of light from a lighting device on a road during the nighttime or in a tunnel based on the presence of a moving body such as a person or a vehicle (refer to, for example, Japanese Laid-Open Patent Publication No. 2009-54496).
The lighting control system of Japanese Laid-Open Patent Publication No. 2009-54496 includes a plurality of lighting devices provided with vehicle sensors that detect vehicles traveling along a road. The lighting devices are arranged along the road, or the travelling direction of vehicles. Each lighting device includes a communication unit that sends and receives vehicle detection information to and from other vehicle sensors. Further, each lighting device includes a control unit that controls the activation of a light source.
Each control unit activates the light source of the corresponding lighting device when the vehicle sensor detects a vehicle. Further, the control unit activates the light sources of the other lighting devices arranged along the travelling direction of the vehicle. When the vehicle sensor does not detect a vehicle, the light source remains deactivated. This decreases power consumption as compared to when the light source is constantly activated.
To further decrease power consumption, recent lighting control systems shorten the actuated time of a vehicle sensor that detects the presence of a moving body. However, when the actuated time of the sensor is shortened, a moving body is detected only when the sensor is actuated. As a result, the light source may not be accurately activated. For example, when the presence of a vehicle cannot be detected due to the short actuation time of the sensor, the light source may not be activated, the time until the presence of a moving body is detected may be lengthened, and the time for activating the light source may be lengthened.